Highly Crystalline Single-Walled Carbon Nanotube Field Emitters: Energy-Loss-Free High Current Output and Long Durability with High Power

Abstract

Power consumption reduction and energy savings for field-emission (FE) electron sources for the loading of high current output, long durability, and high power are considerably challenging in the field of materials. Here we show a new approach using a simple structure comprising highly crystalline single-walled carbon nanotubes (SWCNTs) in the cathode for meeting these goals of power consumption and energy efficiency. Efficacy and applicability were successfully demonstrated by revealing the ideal FE properties of SWCNTs via the control of their crystallinity. The FE fluctuation and emission lifetime of highly crystalline SWCNTs exhibited good stability for greater than 1300 h at 30 mA/cm2 and durability with an FE high current density of 10 A/cm2 via the application of a direct current constant voltage in the cathodic planar field emitter. Moreover, field emitters using highly crystalline SWCNTs permitted the use of new vacuum power switches for the loading power operation of greater than 27 kW, with a high loading current without energy loss and a cooling system. Highly crystalline SWCNTs as a flat plane-emission device can serve as a technological breakthrough for realizing energy savings and a low-carbon society in daily life.

Nanometer-Thick Crystalline Carbon Films Having a Spinel Structure Grown on ZnO Substrates: Implications for New Ceramic–Carbon Composition

“…Compared with thermal electron beams, the FE electron beam can achieve a narrower energy distribution in accordance with the principle of FE 36 and can efficiently emit a large number of electrons with a large amount of electron irradiation (current) at a low voltage. 37 To emit electrons more efficiently at a lower driving voltage, we used highly crystalline single-walled carbon nanotubes (hc-SWCNTs) for the electron source. This is because hc-SWCNTs are expected to achieve stable FE and are suitable for arbitrarily controlling the amount of FE from pA to A order.…”

“…This is because hc-SWCNTs are expected to achieve stable FE and are suitable for arbitrarily controlling the amount of FE from pA to A order. 37 We added hc-SWCNTs to a conductive thin film to form a planar FE electron source and constructed a system for forming a nonequilibrium excitation reaction field. Figure 9 a shows a schematic of the system.…”

“…In this study, an FE electron beam was used to form a nonequilibrium excitation reaction field. Compared with thermal electron beams, the FE electron beam can achieve a narrower energy distribution in accordance with the principle of FE and can efficiently emit a large number of electrons with a large amount of electron irradiation (current) at a low voltage . To emit electrons more efficiently at a lower driving voltage, we used highly crystalline single-walled carbon nanotubes (hc-SWCNTs) for the electron source.…”

“…To emit electrons more efficiently at a lower driving voltage, we used highly crystalline single-walled carbon nanotubes (hc-SWCNTs) for the electron source. This is because hc-SWCNTs are expected to achieve stable FE and are suitable for arbitrarily controlling the amount of FE from pA to A order . We added hc-SWCNTs to a conductive thin film to form a planar FE electron source and constructed a system for forming a nonequilibrium excitation reaction field.…”

Nonthermal Crystalline Forming of Ceramic Nanoparticles by Non-Equilibrium Excitation Reaction Field of Electron

“…In order to realize uniform planar electron emission as a non-equilibrium reaction field, it is essential to employ highly crystalline single-walled carbon nanotubes (hc-SWCNTs) in electrical devices as field emitters, and the effect of increasing the crystallinity of SWCNTs on electrical properties has been investigated [20,21]. We employed hc-SWCNTs as field emission (FE) electron sources with a weight density of less than 1.3 mg/cm 2 and fabricated electrodes on graphite plates by electrostatic coating method.…”